Coating material



Patented Dec. 13, 1932 UNITED stares PATENT OFFICE m DEENISS AND ANDREAS mLSEN', F HAMBURG, GERMANY ASSIGNORS '.I!O m FIRM NEW-YORK HAHIBUBGER GUMMIWAAREN GOMPAGNIE, OF HAMBURG, GER- IANY, A. COMPANY INCORPORATED IN GERMANY 1 COATING IA'IERIAL Ho Drawing. Application fled April 14, 1981, Serial No. 530,128, and in Germany April 8, 1929.

This invention relates to an improved coating having chemically resistant and electrically insulating properties. Substances such as tar, tar-pitch, asphalt and other 5 bitumina have long been used for the production of anticorrosive protective coatings for, for instance, metal, cement and concrete, but particularly for metal surfaces which are to be insulated against the effects of stray currents, for instance, gas and water pipes. These coatings have not proved satisfactory in as much as said coatings, when of the requisite thickness to make a mechanical covering and to exclude the air or corrosive liquids, exhibit a tendency to flow, particular ly at a; somewhat elevated temperature, so

that said coatings had frequently to be held in the position at which they were to be effective by being bound with jute, wool-felt 2 and the like. Moreover the electrical insulating properties of such coatings, particu larly when they have a'high content of free carbon, are not very good.

According to the present invention such 2 coatin 'materials may be substantially improve if they are employed in conjunction with chlorinated rubber solutions. On evaporation of the solvent from chlorinated rubber solutions the chlorinated rubber is left as a 39 'very hard brilliant layer which is chemically inert towards all reagents which need be considered and also constitutes an excellent electrical insulating material. Any desired quantity of a bituminous substance such as 5 tar, tar-pitch, asphalt or the like maybe dissolved with chlorinated rubber in an appropriate solvent, e. g. solvent benzene. After evaporation of the solvent these mixtures yield coatings which are characterized on the 49 one hand by ample hardness andchemical inertness and on the other hand by particularly high electrical insulating powers.

Naturally filling agents, particularly inorganic substances such as very finely ground asbestos, kieselguhr or the like may also be ance for gas and water pipes laid underground and exposed to the action of rust and, particularly, to electric currents. They can thus be used with advantage in any case where rust-protection or mechanical and eleci trical insulation are required.

The following proportions of the materials used are found to be satisfactory:

4 Ewa/mpleI v I Chlorinated rubber L 100 Distillated tar 100 Benzene 200 Ewamplefl p Chlorinated rubber 100 Distillated tar 150 Benzene 200 Ewample3 Chlorinated rubber 100 Bitumina. 50 Benzene V 200 Ewample I Chlorinated rubber 100 Tar-pitch 100 Powdered asbestos l 150, Benzene 200 Having now particularly described and 'aseertained the nature of our said invention, andin what manner the same is to be performed, we declare that what we claim is 1. An insulating coating material comprising a mixture of chlorinated rubber and a bituminous substance selected from the group consisting of tar, tar-pitch, and asphalt.

2. An insulating coating material comprising a mixture of chlorinated rubber and tar.

5 3. An insulating coating material comprising a mixture of chlorinated rubber and asphalt.

4. An insulating coating material comprising a mixture of chlorinated rubber and tar 0 pitch. a

MAX DESENISS.

ANDREAS NIELSEN. 

